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Message-ID: <cf055d45-8970-4657-ab86-d28636645c81@linaro.org>
Date:   Wed, 6 Dec 2023 15:38:50 +0100
MIME-Version: 1.0
User-Agent: Mozilla Thunderbird
Subject: Re: [PATCH v1] thermal: trip: Send trip change notifications on all
 trip updates
Content-Language: en-US
To:     "Rafael J. Wysocki" <rjw@rjwysocki.net>,
        Linux PM <linux-pm@vger.kernel.org>
Cc:     Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>,
        Zhang Rui <rui.zhang@intel.com>,
        Linux ACPI <linux-acpi@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Lukasz Luba <lukasz.luba@arm.com>
References: <5737811.DvuYhMxLoT@kreacher>
From:   Daniel Lezcano <daniel.lezcano@linaro.org>
In-Reply-To: <5737811.DvuYhMxLoT@kreacher>
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Hi Rafael,

On 05/12/2023 20:18, Rafael J. Wysocki wrote:
> From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> 
> The _store callbacks of the trip point temperature and hysteresis sysfs
> attributes invoke thermal_notify_tz_trip_change() to send a notification
> regarding the trip point change, but when trip points are updated by the
> platform firmware, trip point change notifications are not sent.
> 
> To make the behavior after a trip point change more consistent,
> modify all of the 3 places where trip point temperature is updated
> to use a new function called thermal_zone_set_trip_temp() for this
> purpose and make that function call thermal_notify_tz_trip_change().
> 
> Note that trip point hysteresis can only be updated via sysfs and
> trip_point_hyst_store() calls thermal_notify_tz_trip_change() already,
> so this code path need not be changed.

Why the ACPI driver is not calling thermal_zone_device_update() after 
changing the trip point like the other drivers?

It would make sense to have the thermal framework to be notified about 
this change and check if there is a trip violation, no ?


> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> ---
> 
> Depends on https://lore.kernel.org/linux-pm/12337662.O9o76ZdvQC@kreacher/
> 
> ---
>   drivers/acpi/thermal.c                                       |    7 +++--
>   drivers/thermal/intel/int340x_thermal/int340x_thermal_zone.c |    8 +++---
>   drivers/thermal/thermal_sysfs.c                              |    4 +--
>   drivers/thermal/thermal_trip.c                               |   14 ++++++++++-
>   include/linux/thermal.h                                      |    2 +
>   5 files changed, 27 insertions(+), 8 deletions(-)
> 
> Index: linux-pm/drivers/thermal/thermal_sysfs.c
> ===================================================================
> --- linux-pm.orig/drivers/thermal/thermal_sysfs.c
> +++ linux-pm/drivers/thermal/thermal_sysfs.c
> @@ -146,9 +146,9 @@ trip_point_temp_store(struct device *dev
>   				goto unlock;
>   		}
>   
> -		trip->temperature = temp;
> +		thermal_zone_set_trip_temp(tz, trip, temp);
>   
> -		thermal_zone_trip_updated(tz, trip);
> +		__thermal_zone_device_update(tz, THERMAL_TRIP_CHANGED);
>   	}
>   
>   unlock:
> Index: linux-pm/drivers/thermal/thermal_trip.c
> ===================================================================
> --- linux-pm.orig/drivers/thermal/thermal_trip.c
> +++ linux-pm/drivers/thermal/thermal_trip.c
> @@ -152,7 +152,6 @@ int thermal_zone_trip_id(struct thermal_
>   	 */
>   	return trip - tz->trips;
>   }
> -
>   void thermal_zone_trip_updated(struct thermal_zone_device *tz,
>   			       const struct thermal_trip *trip)
>   {
> @@ -161,3 +160,16 @@ void thermal_zone_trip_updated(struct th
>   				      trip->hysteresis);
>   	__thermal_zone_device_update(tz, THERMAL_TRIP_CHANGED);
>   }
> +
> +void thermal_zone_set_trip_temp(struct thermal_zone_device *tz,
> +				struct thermal_trip *trip, int temp)
> +{
> +	if (trip->temperature == temp)
> +		return;
> +
> +	trip->temperature = temp;
> +	thermal_notify_tz_trip_change(tz->id, thermal_zone_trip_id(tz, trip),
> +				      trip->type, trip->temperature,
> +				      trip->hysteresis);
> +}
> +EXPORT_SYMBOL_GPL(thermal_zone_set_trip_temp);
> Index: linux-pm/include/linux/thermal.h
> ===================================================================
> --- linux-pm.orig/include/linux/thermal.h
> +++ linux-pm/include/linux/thermal.h
> @@ -289,6 +289,8 @@ int thermal_zone_for_each_trip(struct th
>   			       int (*cb)(struct thermal_trip *, void *),
>   			       void *data);
>   int thermal_zone_get_num_trips(struct thermal_zone_device *tz);
> +void thermal_zone_set_trip_temp(struct thermal_zone_device *tz,
> +				struct thermal_trip *trip, int temp);
>   
>   int thermal_zone_get_crit_temp(struct thermal_zone_device *tz, int *temp);
>   
> Index: linux-pm/drivers/acpi/thermal.c
> ===================================================================
> --- linux-pm.orig/drivers/acpi/thermal.c
> +++ linux-pm/drivers/acpi/thermal.c
> @@ -294,6 +294,7 @@ static int acpi_thermal_adjust_trip(stru
>   	struct acpi_thermal_trip *acpi_trip = trip->priv;
>   	struct adjust_trip_data *atd = data;
>   	struct acpi_thermal *tz = atd->tz;
> +	int temp;
>   
>   	if (!acpi_trip || !acpi_thermal_trip_valid(acpi_trip))
>   		return 0;
> @@ -304,9 +305,11 @@ static int acpi_thermal_adjust_trip(stru
>   		acpi_thermal_update_trip_devices(tz, trip);
>   
>   	if (acpi_thermal_trip_valid(acpi_trip))
> -		trip->temperature = acpi_thermal_temp(tz, acpi_trip->temp_dk);
> +		temp = acpi_thermal_temp(tz, acpi_trip->temp_dk);
>   	else
> -		trip->temperature = THERMAL_TEMP_INVALID;
> +		temp = THERMAL_TEMP_INVALID;
> +
> +	thermal_zone_set_trip_temp(tz->thermal_zone, trip, temp);
>   
>   	return 0;
>   }
> Index: linux-pm/drivers/thermal/intel/int340x_thermal/int340x_thermal_zone.c
> ===================================================================
> --- linux-pm.orig/drivers/thermal/intel/int340x_thermal/int340x_thermal_zone.c
> +++ linux-pm/drivers/thermal/intel/int340x_thermal/int340x_thermal_zone.c
> @@ -225,7 +225,8 @@ EXPORT_SYMBOL_GPL(int340x_thermal_zone_r
>   
>   static int int340x_update_one_trip(struct thermal_trip *trip, void *arg)
>   {
> -	struct acpi_device *zone_adev = arg;
> +	struct int34x_thermal_zone *int34x_zone = arg;
> +	struct acpi_device *zone_adev = int34x_zone->adev;
>   	int temp, err;
>   
>   	switch (trip->type) {
> @@ -249,14 +250,15 @@ static int int340x_update_one_trip(struc
>   	if (err)
>   		temp = THERMAL_TEMP_INVALID;
>   
> -	trip->temperature = temp;
> +	thermal_zone_set_trip_temp(int34x_zone->zone, trip, temp);
> +
>   	return 0;
>   }
>   
>   void int340x_thermal_update_trips(struct int34x_thermal_zone *int34x_zone)
>   {
>   	thermal_zone_for_each_trip(int34x_zone->zone, int340x_update_one_trip,
> -				   int34x_zone->adev);
> +				   int34x_zone);
>   }
>   EXPORT_SYMBOL_GPL(int340x_thermal_update_trips);
>   
> 
> 
> 

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